Brief introduction of six-point method for laying flat high points

Briefly describe the arrangement of 6-point leveling points as follows:

The six-point method arranges a pair of flat high points in the upper, lower and lateral overlapping range according to the image principal points at the two ends and the center of each section of the gas belt network. The number of baselines between a pair of points at both ends of each aerial strip network varies according to different photographic scales and map scales. It is suitable for nonlinear correction of gas belt network with incomplete bivariate quadratic polynomial.

In photogrammetry, it is necessary to have a certain number of known control points in the overlapping range of each photo or stereo image to correct various deviations of photos and connect them with ground coordinates. According to the layout mode, the layout scheme of photo control points can generally be divided into route network layout, regional network layout and special situation layout. According to the operation mode of image control point layout, it can be divided into full view layout and non-full view layout.

Introduction to photography:

The word photography comes from the Greek word φ? English: phos (light) and γ ρ α φ ι English: graphis (painting, sketch) or γ ρ α φ? Graphê together means "painting with light". Photography refers to the process of recording images with some special equipment. Generally, we take photos with mechanical cameras or digital cameras.

Sometimes photography is also called photography, that is, the process of exposing a photosensitive medium by using the light emitted or reflected by an object. Someone once said an incisive language: the photographer's ability is to transform the fleeting ordinary things in daily life into immortal visual images.

Post production:

After photography is completed, the image information stored in the medium must be read by human eyes again through conversion. The specific method depends on the photosensitive means and medium characteristics. For film cameras, there will be chemical processes such as fixing, developing and enlarging. For digital cameras, pictures need to be processed by computers and then output by other electronic devices.

Exposure process:

When taking pictures, light enters the cassette through a small hole (more often, a lens group) and forms an image on the medium on the back of the cassette (relative to the incident direction of light). According to the actual light intensity and the photosensitive ability of the medium, the required light time is also different. In the process of lighting, the medium is irradiated by light.